Resveratrol tetramers

Seya et al. describe the isolation of additional resveratrol tetramers, as Vitisin A 67 with cardiomyocyte apoptosis activity (09MI90) for more dimeric resveratrols, cf. (08MI507). 

Guebailia, H. A., Chira, K., Richard, T., Mabrouk, T., Euriga, A., Vitrac, X., Monti, J. R, Delaunay, J. C., Merillon, J. M. (2006). Hopeaphenol The first resveratrol tetramer in wines from North Africa. J. Agric. Food Chem., 54, 9559-9564. 

Grandiphenols A and B (676, 677) from the stem of Dipterocarpus grandiflorus have the partial structures of a tetrahydrofuran moiety and two dihydrobenzofuran moieties [219]. The resveratrol tetramer halophilol B (679) isolated from the seeds of Iris halophila is the first isolation of stilbeneoligomer from the family of Iridaceae [35]. 

In addition to the above mentioned timers 600-602 from the stem of Kobresia nepalensis, four resveratrol tetramers, nepalensinols B, E-G (709-712), were isolated from the same plant [293,294]. Among them, nepalensinol B (709) has the same structure as stenophyllol C nepalensinol E (710) has the same planar structure as that of kobophenol A and nepalensinol F (711) is a stereoisomer of hopeaphenol. Some stereoisomers have been reported for hopeaphenol compounds 716, 717 [209], pauciflorol C (713) [208] and vateriaphenol B (714) [323]. Among them, 716 and 717 possess a symmetrical plane, as does nepalensinol F (711). However, the NMR data for 711 did not agree with those for 716 and 717. Although the stereochemistry of H-7c and H-8c in 714 was deduced as a and P in the paper [323], the correct structure of 714 is >ff(H-7c) and a(H-8c), as described in the text. Thus, the relative stereochemistry of 711 is different from that of 714. 

Upuna bomeensis (Dipterocarpaceae) afforded many resveratrol tetramers such as upunaphenols B-D, F, G and H—J, together with trans-and cfr-upunaphenol K (720-729) [212,305,305]. Compounds 725-727 bear a biphenyl bond in their frameworks 725 and 726 have an... 

S (-)-vitisifuran B resveratrol tetramer, G-A Vitis vinifera Kyohou 233... 

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